West Basin is committed to environmental stewardship through minimizing all environmental impacts by implementing a responsible ocean water desalination program. West Basin’s ocean water desalination program has been a step-wise approach since 2002. West Basin has applied and received over $3,000,000 in grant funding from various federal, state, local and research agencies to fund environmental protection studies and the facilities to study them. The over $3,000,000 in grants received has allowed West Basin to be mindful of rate payer spending while still dedicating significant resources and effort to studying environmental impacts. West Basin has completed, funded and participated in 20 ocean water desalination studies to date. Of these studies nine were partially funded by grants from United States Bureau of Reclamation, California Department of Water Resources, Metropolitan Water District of Southern California, Water Reuse Research Foundation and Water Research Foundation .
West Basin Ocean Water Desalination Impingement and Entrainment Study
West Basin Desalination Demonstration Wedge Wire Screen in Operation
Marine impacts from the waste (brine) discharge can be significant if a proper discharge technology is not designed. West Basin has performed several research studies on the impacts of high salinity brine from the discharge on local marine life. Through these studies West Basin identified there is a point in which marine organisms are not impacted by higher brine levels. The No Observable Effects Concentration (NOEC) level for West Basin is 42.5 mg/L of salts in the brine. For reference, the existing ocean water salt level is between 33-36 mg/L depending on the year. West Basin performed the High Salinity Sensitivity(HSS) Study which included a certified Environmental Protection Agency (EPA) lab test called a Whole Effluent Toxicity (WET) test to determine the NOEC.
In addition to the WET test West Basin was the first in the world to develop and run a mesocosm aquarium observation component as a part of the HSS Study. This mesocosm was developed to recreate the ocean environment local to the West Basin service area in two large side-by-side aquariums populated with local marine life. One aquarium was fed fresh ocean water and the other aquarium was fed with brine directly from the desalination process and would be identical to the brine that would be discharged from a full scale ocean water desalination facility. This test allowed West Basin and marine biologists to real time monitor organisms for up to two weeks in both aquariums and determine any impacts resulting from the brine exposure. The results from the mesososm were included in the HSS Study and replicated the results found in the WET test. All the results regarding the salinity impacts on marine life can be found in West Basin’s HSS Study here.
In order to make sure all organisms are within the NOEC level or the “safe zone” salinity range with no impact to marine life, rapid mixing of the brine is key. Rapid mixing of the brine minimizes any potential for a salt water plume to sink to the bottom of the ocean and reduces total contact time of the organisms and the brine plume. This mixing is created using brine diffusers, similar to diffusers that can be found in wastewater treatment plant discharges and other discharges around the world. The State Water Resources Control Board adopted the new desalination policy on May 5th, 2015 stating brine diffusers are the best available technology if the possibility of being able to mix the brine with an existing wastewater outfall is not possible. West Basin has completed research on the rapid mixing of brine diffusers and determined within 2.5 meters (7.5 feet) of the discharge port the salinity is within 5% of normal salinity, or 34.7 mg/l – 37.8 mg/l. The findings on different diffusers designs and ocean modeling can be found in the Brine Diffuser Entrainment Study.
Impacts on the environment from the energy associated with an ocean water desalination facility are typically categorized and quantified as Green House Gasses(GHGs). West Basin has completed several research studies dedicated to reducing the total energy consumption of a full scale desalination facility and in turn reducing the total carbon footprint of the facility. West Basin utilizes all of the latest energy recovery and reducing technologies available and through the Ocean Water Desalination Demonstration Facility (Demonstration Facility) tested new and emerging technologies. West Basin was the first agency to develop an Energy Consumption Modeling Tool, called DORIS, to predetermine energy consumption and GHG emissions before a facility is even built based on West Basin real time operating data. The tool can be found on our Research Page and is available for free download. Through energy recovery devices utilized on site at the Demonstration Facility West Basin was able to reduce energy consumption of the total desalination facility by 30% compared to a facility with no energy recovery.
In addition to having identified, studied and quantified the energy required for operation of a desalination facility West Basin utilized renewable energy in the form of solar panels at the Demonstration Facility. West Basin is exploring the potential to power as much of the full scale ocean water desalination facility with renewable power, such as solar, as much as possible. West Basin remains committed to responsible ocean water desalination by making environmental stewardship a top priority.
In addition to the environmental research, West Basin is committed to responsible ocean water desalination education and constructed an award winning Water Education Center in Redondo Beach, CA. To date, over 50,000 visitors have toured the facility to learn about West Basin’s water supply portfolio and how responsible ocean water desalination is integrated. The education center is still open and available for public and private tours. Throughout this time West Basin has over 10,000 supporters of the Water Reliability Program which includes responsible ocean water desalination. If you are interested in a tour of the Water Education Center click here and fill out the online form. We will be in contact with you to schedule a time for you to learn all about West Basin’s responsible ocean water desalination efforts.